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A (not so) short overview of the Geographic Information System GRASS
By Matteo Dell'Omodarme and Giada Valle
The aim of this article is to introduce the GRASS GIS software and to show its basic usage. As with all GIS software, it is quite complex: there is a huge number of features and controls, and non-trivial theoretical information is required even for basic use. Nevertheless, we think that the quick introduction presented here could be of some help for neophyte users who want to master a GIS program.
We chose to devote a large part of this article to practical use of the software, in particular to real data gathering, reprojection of maps, and output of results. The decision is motivated by the fact that it is very difficult (and in some case impossible) to find this information systematically presented on the Net. Conversely, the introduction to the interface and the ancillary theoretical information are touched upon only briefly, because they can be retrieved from many sources (see the section at the end of this document.)
Since there are so many topics to introduce, and since we do not want to sacrifice clarity to brevity, some topics (i.e., climatological map-making, interfacing GRASS with statistical software, etc.) are postponed until another article.
A Geographic Information System (GIS) is software for gathering, storing, managing, and presenting data that are geographically referenced. The characteristic of a GIS is the capability of examining different sets of geo-referenced data and reaching a conclusion about the existing relationship among the data. In other words, a GIS can link information that is difficult to associate by other means.
For example, it is possible to relate some geo-referenced information (e.g., disease foci) with other data (e.g., location of urbanized and rural zones, climatological data). This can reveal new information that can lead to better decisions about attempting to control the disease's spread.
Nowadays, GIS software is used in several scientific fields, including resource management, environmental impact assessment, ecology, archaeology, cartography, and epidemiology.
GISes are normally capable of different types of spatial analysis and geographical feature processing. Some examples:
- Topological overlay: software can overlap the elements of two thematic maps to create a new map (e.g., users can superimpose the boundary of a natural park with the boundaries of municipalities to determine the areas of responsibility of administration for each of these);
- Buffering: the possibility of defining areas within a given distance from an element (e.g., lake, hill, river);
- Network analysis: algorithms that, given a network of elements (e.g., roads), determine the minimum routes between two points;
- Geostatistic analysis: analysis of the correlation between geographically referenced variables (e.g., altitude vs. humidity).
Geographic Resources Analysis Support System (GRASS) GIS (http://grass.osgeo.org/) is a geographic information system released under the GNU General Public License (GPL). GRASS is being developed for the GNU/Linux, Mac OS/X, and Windows operating systems. GRASS development is split into stable and development branches. The first one is recommended for most users.
GRASS is capable of data management, image processing, graphics production, spatial modeling, and visualization of many types of data. It's an official project of the Open Source Geospatial Foundation (http://www.osgeo.org/).
GRASS was originally developed by the U.S. Army Construction Engineering Research Laboratories (USA-CERL) as a tool for land management and environmental planning by the military. From 1982 to 1995, USA-CERL led the development of GRASS, with the involvement of numerous others, including universities and other federal agencies.
In 1995, the software's development was taken over by a group formed at Baylor University. In this period, the package was ported to Linux. In 1998, Markus Neteler, current project leader, announced the release of GRASS 4.2.1, offering major improvements including a new graphical user interface. In October 1999, the license of the originally public-domain GRASS software was changed to GNU GPL (specifically, starting with GRASS v. 5.0). Users interested in additional historical background can look at http://grass.osgeo.org/devel/grasshist.html.
GRASS has now evolved into a powerful utility, with a wide range of applications. It is currently used in academic institutions and commercial companies around the world, as well as many governmental agencies and environmental consulting companies.
1.1 Basic features and documentation
Upon starting GRASS, the user is presented with a Unix shell containing a modified environment supporting execution of GRASS commands (known as modules). Users can also interface with the majority of GRASS modules and capabilities through a graphical user interface (GUI). There are over 200 core GRASS modules included, and over 100 add-on modules contributed by users and offered on the GRASS Web site. The GRASS libraries and core modules are in C, while other modules are in C, Unix shell, Tcl, or other scripting languages.
Data managed by GRASS can be roughly divided into geometric and attribute data. In the first case, there are:
- Raster data. Data continuously spread in space, structured in a matrix of quadratic cells. Each cell gets an attribute (e.g., temperature, humidity, height, land use code, etc.) Remote sensing (e.g., infrared images of aerial operations) and satellite photographs are classical examples. Raster data are not associated with neighborhood relationships because each pixel is defined by itself.
- Vector data. Used for storage of information about lines and homogeneous areas defined by closed lines. A line connects two end points, identified by their coordinates. State boundaries are an example of such data. Each vector object can be associated with several attributes.
Attribute data are attributes interconnected with the data types mentioned above. For example, a vector layer representing countries boundaries can be associated with data concerning state population, country identification code, etc. Data are usually saved within GIS or in a database system coupled with GIS.
GRASS supports an extensive range of raster and vector formats through binding to GDAL/OGR libraries. GRASS release 6 introduces a new topological 2D/3D vector engine, and support for vector network analysis. Attributes are usually managed in .dbf database files, although other DBMSes can be used. The system is capable of visualizing 3D vector graphics data.
A huge amount of information, documentation, and other resources are available for GRASS. The documentation includes a very useful internal help system, a FAQ list, and a number of textbooks. In addition to the textbooks (http://grass.osgeo.org/gdp/books.php), the GRASS documentation Web page also hosts various user-contributed documentation, such as tutorials and courses (http://grass.osgeo.org/gdp/tutorials.php) as well as manuals (http://grass.osgeo.org/gdp/manuals.php).
Other GIS software is available, both open source and proprietary. Among the former, GRASS is the most widely used, especially for academic research. As for commercial products, the ArcInfo workstation from ESRI and Mapinfo Professional from PitneyBowes Mapinfo are the market leaders. The license price is 9,000-15,000 USD (depending on features) for ArcInfo and about 1,700 USD for Mapinfo. Both programs have been developed for Windows, GNU/Linux, and Unix operating systems but lack support for Mac OS/X.
1.2 Installing GRASS
The latest version can be found at the GRASS download page. Here, you can find precompiled binaries for several platforms as well as the source code.
Installation from source requires at least two extra libraries: PROJ4 for management of projections and GDAL/OGR for reading and writing various GIS data formats. These libraries must be installed in the right order, before installing GRASS.
The first step is to download PROJ4 from http://trac.osgeo.org/proj/. The latest version of the library is 4.6.0. The installation procedure is straightforward:
tar zxf proj-4.6.0.tar.gz cd proj-4.6.0/ ./configure make make install
This library allows management of map projections, which are any method used in cartography to represent the two-dimensional curved surface of the Earth or another body on a plane. Flat maps could not exist without map projections, because a sphere cannot be laid flat over a plane without distortions. To run a GIS package, some details about this topic are required. Some basic elements are given in the following:
The second step is installing the GDAL/OGR library combination. The latest version (1.5.2) can be downloaded from http://download.osgeo.org/gdal. The install procedure is, again, the usual one:
tar zxf gdal-1.5.2.tar.gz cd gdal-1.5.2/ ./configure make make install
GDAL is a translator library for raster geospatial data, while the OGR library (which lives within the GDAL source tree) provides a similar capability for simple-features vector data. These libraries allow import and exchange of files between different GIS programs.
Finally, GRASS can be installed. The last stable version of the software (currently 6.2.3) is located at the GRASS download page. The software is installed by the now-familiar method:
tar zxf grass-6.2.3.tar.gz cd grass-6.2.3/ ./configure make make install
1.3 Running GRASS
As a first step, the user is required to create a directory (GRASS database) that will hold the GRASS data. A usual choice is to create a directory named 'GRASS' (or 'grassdata') in the user's HOME directory.
A subdirectory tree, named location, is automatically created in the GRASS database for each defined project region. All project data are saved in the location subdirectory. The location can be further subdivided into map subdirectories called mapsets.
All general information about the project area is stored within the location in the PERMANENT mapset, which is automatically generated by GRASS. A user can create one or several mapsets for a given location. They can have the extent of the whole project or smaller. This characteristic makes it possible to have several users working on one project at the same time, without the risk of destroying each other's data. Other information about the tree structure of a location can be found, for example, at http://www.gdf-hannover.de/lit_html/grass60_v1.2_en/node10.html.
GRASS can then be started by typing the following at the shell prompt:
The program opens a modified shell and displays the following text:
WELCOME TO GRASS Version 6.2.3 2007 1) Have at your side all available GRASS tutorials 2) When working on your location, the following materials are extremely useful: - A topo map of your area - Current catalog of available computer maps 3) Check the GRASS Web pages for feedback mailing lists and more: http://grass.itc.it/ http://grass.ibiblio.edu/ Hit RETURN to continue
After the user presses Enter, GRASS displays a graphical window from which one can choose the location and the mapset to open, as in the following figure:
From this window, one can read two important pieces of data:
- The database directory of the software (e.g., /home/matt/GRASS) where all the GIS data reside.
- The available locations in the database directory. In this case, there are 4 locations.
Besides choosing a defined location, it is also possible to create a new location in three different ways. These methods differ in the amounts of information required of the user. The simplest case occurs when data about the location are self-contained in the imported map (geo-referenced file); in these cases, no other information is needed.
The definition of a new location requires input (directly by the user or indirectly from a map) of the following information:
- the coordinate system for the location;
- the minimum and maximum coordinates of the area of interest; and
- the ground resolution.
These settings are critical for correct display and management of the location. Therefore, before going further, it's worthwhile to introduce some theoretical information about projections and coordinate systems.
1.4 Excursus: projections and coordinate systems
In a GIS, the information is stored with coordinates; therefore, a coordinate system has to be specified. For geographical data, the geographic system (the well known latitude and longitude) or a geodetic projection like Universal Transverse Mercator (UTM) or Gauss-Krüger are the usual choices.
The UTM coordinate system is a grid-based method of specifying locations on the surface of the Earth. It differs from the traditional method of latitude and longitude in several respects. The Gauss-Krüger system is similar to the UTM system with only small differences. More details on these coordinate systems can be found in further readings listed in the final section.
To optimize the projection from the geoid into a flat map, the Earth is approximated by an ellipsoid.
Different projections are used because each projection is particularly appropriate for certain uses or areas. For example, a projection that accurately represents the shapes of the continents will distort their relative sizes. GRASS offers predefined projections, as well as the geographic system and the possibility to define a geodetic projection by yourself. In this last case, the projection type, the ellipsoid and the datum (a reference from which measurements are made) for referencing the ellipsoid have to be specified.
1.5 Creating a location: the quest for data
The best way to appreciate the functionality of GRASS is to see it in action on a real case-study. As a first step, let us introduce the usual question that worries every new user: "Well, I have just installed this wonderful software, and I have some geo-referenced data to analyze and relate to geophysical characteristics of my research area. But what about geophysical maps? Where can I get them? What kinds of thematic data are available for my region of interest?"
The answer obviously depends on the analysis you have planned, and on the geographic region of interest. Some frequently desired thematic maps are:
- Elevation data
- Landsat data
- Land use data
- Climatological data
- State boundaries
Let us state clearly that, if you are interested in a very specific and very high resolution map, your only hope is to find this resource for a fee (usually substantially high) from a local agency. Sometimes, these data are distributed in electronic format; otherwise, you have to scan them from the hardcopy, yourself.
If you are instead interested in large-region medium resolution (30 - 100 m) maps, the Net hosts several amazing resources you should use. In the following section, we describe Net sources where this information is available for free download, and how to import them into GRASS.
2. Elevation data
The Shuttle Radar Topography Mission (SRTM) obtained elevation data on a near-global scale to generate the most complete high-resolution digital topographic database of Earth. SRTM consisted of a specially modified radar system flown onboard the Space Shuttle Endeavor during an 11-day mission in February of 2000. The SRTM data are available as 3 arc second (90m resolution). 1 arc second data are available for US. The Global Land Cover Facility provides free access to the data (http://glcfapp.umiacs.umd.edu:8080/esdi/).) The data contains "holes" where water or heavy shadow prevented the evaluation of elevation.
In the following example we show how to obtain elevation data for Tuscany (Central Italy), where we currently live.
Data gathering starts by connecting to the Global Land Cover Facility Web page. In the page, the three ways in which you can access the data (Map Search, Path/Row Search, Product Search) are displayed. Let us choose the first, Map search: the user must choose the desired product in the left panel and select the world region of interest (map on the right). Since we are interested in elevation data, we can choose one among the four available options. Note that GTOPO30 is a global digital elevation model with a horizontal grid spacing of 30 arc seconds, so about ten times less accurate than SRTM data. The first two options are different ways to access the SRTM dataset: the first one allows download of tiles of 1 degree square, while the second accesses WRS-2 tiles to approximate Landsat scenes, which we will introduce in the next paragraph. For reasons that will become clear, we choose to select this second option.
Now, we have to select the geographic region of interest, by clicking on the place panel, just above the world map. In the displayed text box type "Toscana, Italy" and press Enter. (In general, you type "Location, State".) You should then see a page similar to the one displayed in the figure.
There are 35 maps available in the selection. The next step is to select the ones of interest. Having pressed the button "Preview & Download", the selection window is displayed. It looks like the figure below:
The screen is divided into two zones. In the lower one available maps are listed, with their associated information. In particular, you can see the type of data (GeoTIFF format, a widely used raster format), the status (unfinished, unfilled, finished-a, and finished-b in ascending order of processing level and of our choice). In the third column, there are data which allow the identification of path/row attributes, used for Landsat satellite data. The user can select a map by clicking on its ID (first column). In the upper area, information about the selected map is shown. In the right part, the user can check which zone is covered by the map. This picture can guide the selection of really interesting maps. After identification of a desired map, the user should press the download button, and download the .tif.gz file from the window that will open.
At the end of the scan, you will find that only four maps are required for download: ID 180-332 (path/row: 191/030), ID 180-364 (192/029), ID 180-365 (192/030), and ID 180-408 (193/029). These files can be saved in a directory, e.g., $HOME/SRTM, and uncompressed.
2.1 Importing a raster map
GeoTIFF files incorporate information about the coordinate system, the projection, and the datum used for their georeferencing. In this way, it is possible to use them to define a new GRASS location, and subsequently import them into the software.
The process is a little tedious. From the start page of GRASS (displayed in the first figure of this article), define a new location by pressing the button "Georeferenced file". In the window that will open, insert the name of the new location (e.g., "tuscany"), and, in the last one, select the path to one of the four downloaded files (e.g., SRTM_ffB03_p192r029.tif). End the location definition by pressing "Define location". GRASS generates the tree for the new location, and displays a warning requesting to close the program.
At the restart, you will be able to see your first new generated location!
Select the location tuscany, and the mapset PERMANENT, then click on "Enter GRASS". The shell will display the following greeting message:
Welcome to GRASS 6.2.3 (2007) GRASS homepage: http://grass.itc.it/ This version running thru: TC Shell (/bin/tcsh) Help is available with the command: g.manual -i See the licence terms with: g.version -c If required, restart the graphical user interface with: gis.m & When ready to quit enter: exit Mapset <PERMANENT> in Location <tuscany> GRASS 6.2.3 >
Besides that, three more windows will open: the GUI (window GRASS
6.2.3 GIS Manager), the output window which will host the output of
all commands issued by means of GUI, and the map display window.
At this point, the Tuscany location is created, but it hosts no
data. Importation of the four downloaded maps can be performed either
by shell command or by GUI. We illustrate first this second approach,
since it will also show the shell command associated with the GUI
From the GUI menu bar, select File / Import / Raster map / Multiple formats using GDAL. Fill in the form that will open, as in the following figure:
The only required fields are the name of input file and the output name, i.e., the internal name GRASS associates to this map. The box "Extend location extents based on new datasat" will extend the location to encompass the imported map.
In the window's last line, the shell command associated with the import operation gets displayed. Its structure is really simple, and makes it faster to import the other maps from the shell. At the shell prompt, insert these commands:
r.in.gdal -e input=/home/matt/SRTM/SRTM_ffB03_p192r030.tif output=192_030 r.in.gdal -e input=/home/matt/SRTM/SRTM_ffB03_p193r029.tif output=193_029
Unfortunately, trying to import the fourth map, you receive an error:
r.in.gdal -e input=/home/matt/SRTM/SRTM_ffB03_p191r030.tif output=191_030 ERROR: Projection of dataset does not appear to match current location.
What is happening? The answer is simple, as is the solution. The projection information associated with this map is different from the those of the three imported maps. The simpler solution is to import the map in a new location (say, "tuscany2"), which will be created ad-hoc, and then reproject the data in the current location. The first step is accomplished by adding a location parameter to r.in.gdal:
r.in.gdal -e input=/home/matt/SRTM/SRTM_ffB03_p191r030.tif output=191_030 location=tuscany2
Since a map's projection does not extend the region boundaries on the fly, you have to be certain that your region is large enough to contain the projected map. In this case, this is false, because the fourth map is partially outside the east boundary. You have to manually adjust this boundary with the command g.region (Config / Region / Change region settings from GUI), and then reproject (Raster / Develop map / Reproject raster from other location from GUI).
Which value has to be set as the east boundary? To make an educated guess, it is better to look at the coordinates of one of the imported maps. You can do it by setting the boundaries of the location to match one of the maps and then extrapolate where the fourth map will be located. For example:
g.region rast=192_029 g.region -p
The first command sets the location's boundaries to those of map 192_029. The second one queries all of the location's parameters; from its output, we can learn several things, such as coordinate system, projection, datum, and coordinates of the boundaries (Config / Region / Display region settings from GUI):
projection: 1 (UTM) zone: 32 datum: wgs84 ellipsoid: a=6378137 es=0.00669437999014138 north: 5065399.56462278 south: 4821139.56462278 west: 576236.63839707 east: 828866.63839707 nsres: 90 ewres: 90 rows: 2714 cols: 2807 cells: 7618198
In the output above, the measures are in meters. Now it is possible to set the eastern boundary:
g.region e=968866
And reproject the map in the current location:
r.proj input=191_030 location=tuscany2 output=191_030 method=nearest
The syntax of r.proj is self explanatory. The option method chose the interpolation algorithm to be used. (Note: if you set an incorrect east boundary, and you have to reproject the map, you must add the flag --overwrite at the end of command r.proj.)
2.2 Displaying and patching raster maps
It is time to see some output from GRASS! Let us display one of the imported maps, say, 192_029. This is done by using the GUI and pressing the "Add raster layer" button .
A new empty raster layer is then added for visualization in the upper part of the GUI window. By clicking on the name of the layer, you cause the lower part of the window to display a form. Here, you can define which map is associated with the layer. Press on the Base map button, and select the map from the list that is then shown. At the end of the procedure, the GUI should look like this:
You should now admire the results of your work. In the Map display window, press the "Display active layer" button (the first one). The window will probably remain empty. In this case, we have to set the zoom of the displaying window to the one of the region boundaries (which we set in the previous paragraph). You should press on the button "Zoom to..." , and select the option "Zoom to current region" as shown in the figure:
The displayed map should look almost red, with the exception of a few yellow areas, which correspond to the no-data zones. A useful instrument available from the Map Display window is the query button . Select it and then press over the map; the value associated to the cell is shown in the output window. You will discover that, for example, no-data areas are represented by value -32768.
Now it's map-cleaning time! We have to patch the four maps to obtain a new composite map. Before that, we have to clean up the maps. In fact, GRASS expects that no data zones will be identified by a NULL value, while, as we know, SRTM maps identifies no-data areas with the code -32768. The following commands correct this problem (Raster / Develop map / Manage null values from GUI):
r.null map=191_030 setnull=-32768 r.null map=192_029 setnull=-32768 r.null map=192_030 setnull=-32768 r.null map=193_029 setnull=-32768
The next step is definition of the correct location boundaries. GRASS can make boundaries from a series of maps. We use this characteristic by issuing the command:
g.region rast=191_030,192_029,192_030,193_029
The resulting boundaries just encompass the four maps.
As our last step, we can merge the maps, and define an appropriate colormap:
r.patch in=191_030,192_029,192_030,193_029 output=elev r.colors map=elev rules=srtm
The command r.patch (Raster / Overlay maps / Patch maps from GUI) creates a new map, named elev, by merging the four existing ones, while r.colors (Raster / Manage map colors / Set colors to predefined color tables from GUI) defines a colormap using an appropriate predefined ruleset (srtm).
To correctly visualize the map, we have to restart GRASS after having closed the session by entering exit at the shell prompt, and closing the window manager. After having restarted the software, we can display the final result of our work: repeat the procedure used for displaying a raster layer and select the map elev. The map should look like this one:
If the result is satisfactory, you can delete the four small maps. From the GUI, the path is "File / Manage maps and volumes / Remove maps" and fill the raster field with the name of the maps to delete. From the shell, type:
g.remove rast=191_030,192_029,192_030,193_029
At the end of this section, we have created an elevation map for the Central Italy area. We will later extract from it the data related to the Tuscany region, and discard the rest.
As a final note, since the coverage of SRTM data is worldwide, the procedure can be repeated for any location.
3. Landsat data
Landsat-7 is a satellite launched on April 1999. It has sun-synchronous, near-polar orbit that allows it to record the surface of the Earth in a pattern of overlapping 185 km swaths, completing one scan every 233 orbits. The pattern is catalogued as a tiled global grid of 233 paths and 248 rows in the so called Worldwide Referencing System (WRS). We have seen an example of this reference system when downloading SRTM data.
The satellite is equipped with an instrument called the Enhanced Thematic Mapper (ETM+), a multi-spectral radiometric sensor. The sensor records eight bands of data with varying spectral and spatial resolutions (30 m spatial resolution for red, green, blue, near infrared, and two bands of medium infrared; 60 m for thermal infrared; and a 15 m panchromatic band). A list of the bands with their spanned wavelength (in micrometers) is given below:
- Blue-Green: 0.45-0.515 μm
- Green: 0.525-0.605 μm
- Red: 0.63-0.690 μm
- Near infrared: 0.760-0.900 μm
- Medium infrared: 1.550-1.750 μm
- Thermal: 10.40-12.5 μm
- Medium infrared: 2.080-2.35 μm
- Panchromatic: 0.52-0.92 μm
Landsat data are available from many sources. During April 2008, all data gathered by the satellite were released into the public domain, so it is possible to download scenes acquired in different months and different years. (See http://landsat.usgs.gov/products_data_at_no_charge.php for details.) We will show here a simpler method of download, limited at one dataset acquired in the years 2000-2001, available at the Global Land Cover Facility Web page. Data gathering procedure is identical to that described in the previous section. The user must select the right product by checking the ETM+ box in the interface shown in second figure of this document.
The result should be similar to the figure below:
The same path/row maps downloaded for elevation data are required; this correspondence greatly accelerates the user choice. In this case, the map IDs are: ID 036-387, ID 036-429, ID 036-430, and ID 036-128.
By pressing the download button, you can see that the data are available as a set of eight GeoTIFF files (one for each ETM+ band). They are much bigger than SRTM data, since the resolution is about three times as great. You can download whatever band you desire.
Landsat data can be used to assess the type, extent, and condition of vegetation over a region, or vegetative change over time. These studies require that a vegetative index be calculated from sets of remotely-sensed data. The most widely used index is the Normalized Difference Vegetative Index (NDVI). The NDVI is calculated as a ratio between measured reflectivity in the red and near-infrared portions of the electromagnetic spectrum. These two spectral bands are chosen because they are affected by the absorption of chlorophyll in leafy green vegetation and by the density of the green vegetation on the surface. Moreover, in red and near-infrared bands, the contrast between vegetation and soil is at a maximum.
ETM+ bands 3 and 4 provide red and near-infrared measurements, and therefore can be used to generate NDVI data sets with the following formula:
NDVI = (Band 4 - Band 3) / (Band 4 + Band 3)
The NDVI equation produces values in the range of -1.0 to 1.0. Vegetated areas will typically have values greater than zero, and negative values indicate non-vegetated surface features such as barren, water, ice, snow, or clouds. NDVI value are usually scaled for display, as is the following equation:
Scaled NDVI = 100 (NDVI + 1)
3.1 Making a raster map from existing ones
To evaluate the NDVI index for Tuscany, we have to download bands 3 and 4. These files can be saved in a directory, say, $HOME/Landsat, and uncompressed.
In order to preserve the projection values of Landsat data, the data can then be imported in a new location, e.g., landsat, in order to preserve the projection values of Landsat data. As shown in the preceding section, the command (dataset 193/29, band 4) is:
r.in.gdal -e input=/home/matt/GIS/Landsat/p193r029_7t20010801_z32_nn40.tif output=193_29_4 location=landsat
Restart GRASS, enter the new defined location, mapset PERMANENT, and finish the import:
r.in.gdal -e input=/home/matt/GIS/Landsat/p193r029_7t20010801_z32_nn30.tif output=193_29_3 r.in.gdal -e input=/home/matt/GIS/Landsat/p192r029_7t20000620_z32_nn40.tif output=192_29_4 r.in.gdal -e input=/home/matt/GIS/Landsat/p192r029_7t20000620_z32_nn30.tif output=192_29_3 r.in.gdal -e input=/home/matt/GIS/Landsat/p192r030_7t20000620_z32_nn40.tif output=192_30_4 r.in.gdal -e input=/home/matt/GIS/Landsat/p192r030_7t20000620_z32_nn30.tif output=192_30_3
As seen previously, map 191/30 has a different projection, so you have to read that map in a new location (one for each map), extend the region boundaries, and reproject the maps in the current location:
r.in.gdal -e input=/home/matt/GIS/Landsat/p191r030_7t20010803_z33_nn40.tif output=191_30_4 location=landsat2 r.in.gdal -e input=/home/matt/GIS/Landsat/p191r030_7t20010803_z33_nn30.tif output=191_30_3 location=landsat2b g.region e=968866 r.proj input=191_30_4 location=landsat2 output=191_30_4 method=nearest r.proj input=191_30_3 location=landsat2b output=191_30_3 method=nearest
As a last step, we can patch the maps together. Since, in this case, null values are represented by zeroes we can skip the r.null call by adding a -z flag to r.patch:
r.patch -z in=192_29_4,192_30_4,193_29_4,191_30_4 output=Landsat_B4 r.patch -z in=192_29_3,192_30_3,193_29_3,191_30_3 output=Landsat_B3
Now, all the elements for NDVI calculation are on hand. It is time to learn how to make a new map starting from existing ones!
The best approach is to use the shell command r.mapcalc:
r.mapcalc "NDVI=(float(Landsat_B4 - Landsat_B3) / (Landsat_B4 + Landsat_B3) + 1)*100"
To obtain a floating point division (the Landsat maps are integer maps), the float function is required. The command makes a new map, called NDVI, by operating, cell by cell, on the values in maps Landsat_B3 and Landsat_B4.
Finally, you should reproject the NDVI map into the tuscany location. To do that, exit from GRASS session, restart the program, and login into the tuscany location. Then issue the command:
r.proj input=NDVI location=landsat output=NDVI
If no problem arises, you will have two raster maps in this location. To recover disk space, all other locations can be erased. This can be done by exiting GRASS, changing directory to $HOME/GRASS, and deleting the directories tuscany2, landsat, landsat2, and landsat2b. The resulting map will be shown in the next section, once having learned how to "mask" it in order to show only the pixels of Tuscany.
As for SRTM data, Landsat data also is worldwide, so you can repeat the procedure for any location on the Earth.
4. Getting state and districts' boundaries
States', districts' and municipalities' boundaries can be retrieved from several sources, depending on the region of interest. In the case of Italian regions, for example, these are available from the ISTAT Web site (in Italian). The file of interest (regioni) can be downloaded from the right panel. This file contains Italy's regional boundaries.
4.1 Managing a vector map
Download the file into a new directory, e.g., $HOME/IT, then unzip it. The content of the archive consists of several files, one of which is a .shp file, a widely used vector type of data.
To read this type of data into GRASS, proceed in this way. Start GRASS in the tuscany location, then issue the command (File / Import / Vector map / Various formats using OGR from GUI):
v.in.ogr -e dsn=/home/matt/IT/reg2001_s.shp output=reg_boundaries min_area=0.0001 snap=-1 location=italy_reg
The import requires the specification of a datum transformation parameter. At the prompt, you can select parameter 8, valid for whole European area. At the end, you will have a new location, named italy_reg, which will contain a vector map named reg_boundaries.
Now, logout from the GRASS session and restart in the newly created location. The acquired vector map contains political boundaries of all the Italian regions. For our example, only the Tuscany region is of interest, so we have to extract an element from a map. For a vector map, this is a quite simple operation, since it is equivalent to extracting records from a database through a query.
To do the extraction, we should first learn how to inspect the database associated with a vector map. This can be easily done in the GUI. Vector layers are added to the display layer, in a fashion similar to the raster layers. The only change is that users have to press the "Add vector layer" button .
Select the added layer in the top part of the GUI window. In the bottom part, which will become available, choose the vector map you want to display, using the "Vector map" text field or the corresponding button. There are many more options for vector maps than for raster maps. For now, we are interested in the two buttons located at the end of the list. Scroll down the window, and you should see the buttons "show attribute columns" and "show attribute data".
These buttons access the database linked to the map and return, respectively, the names of the database columns and the contents of the whole database, as shown in the next figure where these outputs are displayed. Note that each output is prefaced by the command forwarded from the GUI to the shell interpreter.
The database contains four columns: a key used to index the table, the code of the regions, their names and their populations as recorded in 2001. The region code could be used for extraction of Tuscany. You can do that typing the command:
v.extract in=reg_boundaries out=tuscany_boundaries new=-1 where="COD_REG=9"
The map tuscany_boundaries will be created. The option new=-1 preserves the database table, exporting it in the new map.
4.2 Vector to raster conversion
Before exiting and connecting again in the tuscany location, we'll demonstrate how to convert a vector map to a raster one. This step will create a silhouette of the Tuscany region, which will later help us to "cut" the map of elevation and NDVI to the required extent. The resolution of the vector map is much lower than the one of the tuscany location (check it yourself: g.region -p). So, we increase the resolution and then convert the vector map:
g.region nsres=90 g.region ewres=90 v.to.rast input=tuscany_boundaries output=MASK use=val
This command makes the map MASK (a reserved map name), assigning to all cells the same value (option use=val). When a raster map named MASK exists in a location, most raster operations (on any raster map) will take place only in the grid cells specified by the MASK.
Now, restart GRASS, and access the tuscany location. Then, reproject the vector and the raster maps from italy_reg:
v.proj input=tuscany_boundaries location=italy_reg output=tuscany_boundaries r.proj input=MASK location=italy_reg output=MASK
If we try to display the elev raster map, as we did before, the result is different. The elev map is masked, and only cells from Tuscany will be shown. The same behaviour occurs for NDVI map. The two maps are shown in the following figure (NDVI on the left, elevation on the right).
5. Land cover map
Land cover data are available from different sources, depending on the region of your interest. For European countries, you can refer to Corine Land Cover (CLC). CLC is a map of the European environmental landscape based on interpretation of satellite images; it provides comparable digital maps of land cover for each country for much of Europe, and includes 47 classes of land cover. Data on land cover is necessary for environmental policy, regional development, and agriculture policies.
Corine Land Cover 2000 data can be downloaded at 100 m horizontal resolution in raster format (GeoTIFF) from the European Environmental Agency Web site (http://dataservice.eea.europa.eu/dataservice/metadetails.asp?id=1007). Users are required to complete the "Agreement form for Corine Land Cover 2000", which is shown before download. In this way, you can download the whole European area contained in the file lceugr100_00EEA17938I.zip (approx 66MB). The download page is shown in the following figure. In the same page, you will find the file (four formats are available) containing the legend for interpretation of the map.
There is also the possibility of downloading data in vector format (shapefile .shp), selecting on a grid only the region of interest (see http://www.eea.europa.eu/themes/landuse/clc-download).
After having downloaded the file into a directory, e.g., $HOME/CLC, uncompress it; the files will be expanded in a subdirectory named lceugr100_00. Then start GRASS in the tuscany location and import the data into the new location (e.g., CLC):
r.in.gdal -e input=/home/matt/CLC/lceugr100_00/lceugr100_00_pct.tif output=CLC location=CLC
CLC data can be reprojected in the current location:
r.proj input=CLC location=CLC output=CLC method=nearest
The new raster map can be displayed as shown before. The result is in the following figure; the presence of the raster MASK will cut the map at the desired boundaries.
The various areas are depicted in different colors. The legend for interpretation of the map can be found in the file $HOME/CLC/lceugr100_00/clc_legend.xls. From this file you can see that, for example, CLC code 111 represents Artificial surfaces/Urban fabric/Continuous urban fabric and is depicted in RGB color 230-0-77, while code 221 is Agricultural areas/Permanent crops/Vineyards, and its RGB color is 230-128-0.
After a successful import of the map, you can recover a lot of disk space by erasing the location CLC. This is done by exiting GRASS and deleting the directory $HOME/GRASS/CLC.
5.1 Land cover map of US
When the research area is within the USA, the user can refer to the National Land Cover Database (NLCD 2001). It is an update of NLCD 1992, and includes 21 classes of land cover at 30 m cell resolution. The 76 standard NLCD mapping zones have been grouped into 15 larger zonal areas for easier distribution and download. The download site address is http://www.mrlc.gov/nlcd_multizone_map.php.
This page also contains a link to a zipped shapefile (3 MB) with the standard NLCD zones as well as a multizone attribute. Download it into $HOME/US directory, and unzip its content: a subdirectory named landcover_bndry_030607_shp will be created in the process. There, along with several other files, you'll find the landcover_bndry_030607.shp shapefile, which we'll later import into a new location.
The next step is to download the landcover for the zone of interest: you have the option to download data for a state or a superzone. As an example, let us choose the data for superzone 13 by clicking on it over the displayed US map. In the page that will open, select the link Land Cover zip file, and save the associated file area_13_landcover.zip (130 MB) in the directory $HOME/US, then unzip its content. Among other files, you will see the raster file landcover13_3k_022007.img, which we are going to import into GRASS.
After restarting GRASS in the tuscany location, we can import the superzone 13 raster data into a new location, i.e., USA:
r.in.gdal -e input=/home/matt/US/landcover13_3k_022007.img output=area13 location=USA
The import requires specifying the datum transformation parameter. At the prompt, you can select parameter 6, valid for whole North American region.
Exit GRASS, and restart in the USA location. Then, import the shapefile containing the states' boundaries, and extend the location boundaries to match the ones of the vector map:
v.in.ogr -o dsn=/home/matt/US/landcover_bndry_030607.shp output=boundaries min_area=0.0001 snap=-1 g.region vect=boundaries
Finally, we can display the resulting map, superimposing the vector layer to the raster one. To do that, in the GUI, you can start by adding a raster layer for visualization and selecting the raster map area13. Then, add a vector layer and select map boundaries. Using the vector layer, you can display a variety of objects: points, lines, centroids, and areas. To display only the boundary lines, deselect checkbox centroids and areas, as in the figure below.
Then, activate the Map Display window, and press the display button. The zoomed result should look like this:
The described procedure could be adapted to other locations over the planet. A useful reference for landcover data is http://landcover.usgs.gov/landcoverdata.php.
6. Climatological data
Climatological data open a entirely new way of searching for information. Whereas elevation data can be considered static (i.e., their value does not change with time), and Landsat and land use data evolve slowly in time (in fact, you can find research papers comparing the Landsat situation in various decades to trace the global climate evolution), climatological data change rapidly. So, the first question you have to ask yourself is: "What type of data am I searching for?" You might be interested in daily or even hourly measurements, or in monthly means, or even in seasonal or yearly means. Moreover, yearly and seasonal means can be evaluated over a long period (say, 15 years) to smooth out the fluctuations introduced by a very hot summer or by a very cold winter.
The second aspect to be considered is the format in which data are distributed. The measurements are usually provided in tabular format: the tables contain the values recorded by a set of meteorological stations distributed over the region of interest. The main variables recorded are temperature (minimum, maximum, mean), humidity, and rainfall. Values in places without meteorological stations can be obtained by the user by mean of interpolation techniques. This is a difficult process, and requires a deeper analysis, because it involves either data manipulation (e.g., transformation of daily data in the tables to obtain a seasonal mean; selection of the interesting stations, etc.) or interpolation with advanced statistical techniques (e.g. universal kriging interpolation.) This last step can be performed by, for example, interfacing GRASS with R, a statistical program which we briefly described in issue 138 of the Linux Gazette.
Since a detailed description of all these depicted procedures would be long and complex, we'll postpone it until another article.
Moving further
In this long excursus, we have introduced some basic features of the software, but have neglected almost completely to describe the way in which data could be analyzed and related to each other. This approach is motivated by our experience with GRASS. In fact, when we started using this software, we realized that there are many good tutorials and manuals describing in great detail all the operations possible with the software - but we had a great deal of difficulty in finding and acquiring thematic maps, either because the tutorials are usually focused on a standard dataset (provided as an example of location data with GRASS) or because the information we needed was scattered all over the Net. It is our hope that the present document will contribute to filling this gap.
While waiting for our next article, readers seriously interested in the software can start by browsing the documentation pages available at the GRASS Web site, which also hosts some documents in non-English languages. We recommend the following documents:
- Introduction to GRASS GIS software. http://grass.osgeo.org/gdp/neteler/index.html
- An introduction to the practical use of the Free Geographical Information System GRASS 6.0. http://www.gdf-hannover.de/lit_html/grass60_v1.2_en/index.html (HTML), http://www.gdf-hannover.de/dl.php?download=gdf_grass60_v1.2_en.pdf (PDF)
- GRASS 6 in a nutshell. http://mpa.itc.it/markus/osg05/
Other resources available on the net can be useful:
- Geographic Information System. http://en.wikipedia.org/wiki/Geographic_information_system
- GIS file formats. http://en.wikipedia.org/wiki/GIS_file_formats
- Description of possible projections. http://en.wikipedia.org/wiki/Map_projection
- Universal Transverse Mercator coordinate system. http://en.wikipedia.org/wiki/Universal_Transverse_Mercator_coordinate_system
- Gauss-Krüger coordinate system. http://en.wikipedia.org/wiki/Gauss-Krüger_coordinate_system
- Geographic Information Systems. http://erg.usgs.gov/isb/pubs/gis_poster/
Talkback: Discuss this article with The Answer Gang
Matteo Dell'Omodarme
I am a physicist involved with Linux since 1994, when I acted as system and security manager at the Department of Astronomy, University of Pisa (Italy). My current research interests are mainly in Applied Statistics, but I also work as system manager, net manager, web developer and programmer (C, C++, FORTRAN, Php, Tcl/Tk).
Giada Valle
I am an astrophysicist mainly interested in galactic evolution; in this subject I develop simulation codes in C/C++ and FORTRAN. I've been using Linux since 1998, when I worked on my degree thesis at the University of Pisa (Italy).


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subset: commoncrawl


text:
I negotiate deals and litigate on behalf of producers, writers, actors, distributors and financiers. After 18 years of practicing law in Los Angeles; 16 of them as an entertainment lawyer, I'm taking stock on where I've been, what I've done and what's next.
I'm going to write in this space about the negotiation culture in the entertainment business, my thoughts on practicing entertainment law and whatever else occurs to me from time to time.
I get a lot of inspiration from my late father Norman. He ran his own company in the knitted textile business in New York City. Norman would regale the family with vivid stories of the day's events during dinner. The piece goods business in women's wear was a lot like the entertainment industry. There were a lot of characters; and he would regularly use an "ism" or two – an unusual word or use of slang – that only made the people in his stories more Runyonesque.
I enjoy using a lot of these isms today. I even collect or create new ones. So when I decided to write online, I wanted to use an ism as the name for the blog. "Deal Fatigue" is a common business ism and can be defined as the point in protracted negotiations where one or more of the parties either close on terms that they might not otherwise agree upon just to get the deal done or are ready to walk away despite any benefits that may come from closing.
While deal fatigue is an all too common phenomenon in negotiations, I use the term here as a double entendre. After a career spent in organized combat with lawyers, agents, managers, financiers and yes, sometimes clients, I must admit to being a bit tired. I hope that my reflections here will provide a respite and a unique opportunity to focus my thoughts in a manner that can only be of benefit to my clients and me.


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JBS sophomore Channing Everidge has been selected as a 2012 Rogers Scholar! The Rogers Scholars Program is sponsored by The Center for Rural Development in Somerset. The program is designed to help the Center move toward its vision: "No young person should have to leave their home region to find their future – they can find it right here in Southern and Eastern Kentucky!"
Channing applied during her sophomore year in high school. After being selected through a competitive process, she will be attending the program this summer just prior to the start of her junior year. Channing will be traveling to Somerset and the surrounding area where she will attend events at The Center for Rural Development. She will be staying at a local hotel, and all lodging, meals, and program expenses will be free to her as a selected student.
Channing will be involved in an extensive, weeklong program concentrating on establishing skills in leadership, technology, entrepreneurship, and community service as a future leader in the region. She will interact in fun, educational activities during a week that will be filled with once-in-a-lifetime opportunities. About her achievement, Channing said, "I consider it a great honor to have been selected for the Rogers Scholar Program. I look forward to participating in the group activities and learning new and useful skills."


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23-year veteran of the foodservice industry joins casual-dining brand.
Applebee's Services, Inc. named Steve Layt its senior vice president, operations. A 23-year veteran of the foodservice industry, Layt comes to Applebee's from Buffets Holdings, Inc., where he served as chief operating officer and executive vice president.
Prior to Buffet Holdings, Inc., he served as franchise head coach for Yum! Brands' Pizza Hut Division in the eastern United States.
In his new role Layt will provide strategic direction and focus on day-to-day management of domestic operations for the casual-dining brand.


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Home → Prizes
How to Claim a Prize
Caring for your ticket
Here are some important tips to safe guard your ticket:
- Sign the back of your ticket. Lottery tickets are bearer instruments. Unless signed, anyone in possession of a ticket can file a claim.
- Store your ticket in a safe place until you are ready to claim it. Do not expose your ticket to extreme sunlight or heat such as from irons, dryers or windows.
- Do not laminate your ticket.
- Do not expose your ticket to prolonged time in water such as washing it in a clothes washer.
If a ticket is damaged, a lottery retail agent or the lottery office may still be able to validate your ticket if the barcode or ticket number is still legible.
How to Claim
Prizes under $600 can be claimed at any Maine State Lottery retail agent location.
To claim a prize of $600 or more, you can use any of the methods below to claim your winning ticket. You should make a copy of the front and back of the signed ticket and the completed claim form for your records.
- In-person – Bring your signed winning ticket to the Lottery office in Augusta, Maine to claim your prize. You will need to present a valid form of a government issued identification card such as a driver's license; a passport issued by the United States or a foreign government; an identification card issued by any branch of the armed forces of the United States or an identification card issued by the United States Bureau of Citizenship & Immigration Services.
- By Mail or Courier – Complete this claim form as well as the back of the ticket. You should make a copy of the front and back of the signed ticket, (the claim receipt from option C below, if applicable) and the completed claim form for your records. Please staple the winning ticket to the completed form and mail to the Lottery office. We strongly urge you to send winning tickets by certified or express mail or by other means to track your winning ticket delivery to the Maine State Lottery; or
- In person at a Lottery Retail Agent location – Bring your winning ticket to any location where lottery tickets are sold. The Lottery Retail Agent will validate your ticket and the lottery system will indicate that you must file a claim at the "Lottery Headquarters". The lottery retail agent representative will then present you with a "Claim Receipt" and give you back your original ticket. You must then follow either steps A or B above to complete the claim for your winnings.
For a group claiming a prize
If a group of persons is claiming a winning ticket, each person in the group must complete a claim form. When submitting a winning ticket for claiming as a group, please also indicate how the prize will be divided among the winners. Each winner will receive a check and each person will receive a W-2G tax form at the end of the year for their share of the prize.
Other information to know when you claim your prize
The Maine State Lottery will withhold Federal and State taxes at 24% and 7.15% respectively on prizes over $5000. It is important to understand that the taxes withheld, if any, may not cover your entire Federal or State tax obligations. The final tax amount owed will depend on your personal tax situation. As the Maine State Lottery or its employees cannot provide you with financial advice, you should talk with a professional tax advisor.
The Maine State Lottery is also required to withhold any portions of a claimant's winnings if the claimant owes an outstanding debt to a state agency.
Time for processing claim – Please allow five (5) business days for processing your claim.
Claim Form
The claim form is an Abode Acrobat fillable form that you can download, complete on screen (PDF) and print from your local printer. You can get your free Adobe Reader from the Adobe website.
Address for claiming a prize in person or by courier delivery:
Bureau of Alcoholic Beverages and Lottery Operations
19 Union St
3rd Floor
Augusta, ME 04330
Address for claiming a prize by mail:
Bureau of Alcoholic Beverages and Lottery Operations
8 State House Station
Augusta, ME 04333-0008
For questions regarding claiming a prize, please contact the Maine State Lottery at:
(800) 452-8777 (Maine only)
(207) 287-3721


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And so, if only by remorseless process of elimination, at long last the big A wins the pool. I had Nelson and Ayotte as next to flip in the last SSM thread; there are only something like six Democrats in the Senate who haven't switched yet, so I was bound to be right soon. Kudos to this guy for sparing me the humiliation of missing every call until we were down to one lone Democrat left.
In a statement to the Tampa Bay Times editorial board, he wrote:
It is generally accepted in American law and U.S. society today "… that all Men are created equal, that they are endowed by their Creator with certain unalienable Rights, that among these are Life, Liberty and the Pursuit of Happiness. I believe that. The civil rights and responsibilities for one must pertain to all.
Thus, to discriminate against one class and not another is wrong for me.
If we are endowed by our Creator with rights, then why shouldn't those be attainable by Gays and Lesbians?
Simply put, if The Lord made homosexuals as well as heterosexuals, why should I discriminate against their civil marriage? I shouldn't, and I won't.
So I will add my name to the petition of senators asking the Supreme Court to declare the law that prohibits gay marriage unconstitutional.
He's 70 years old, yet apparently only recently did the insight occur to him that both the Declaration of Independence and God point the way towards gay marriage. I've gotten used to people on my side of this issue treating it as a no-brainer even though many of them held the opposite view not long ago, but I think Nellie might have just raised the bar on latecomer hubris. I guess if you're going to drag your feet, you need to make up for it somehow.
Any more flips coming soon? My hunch is that the pared-down core of Democratic holdouts won't easily be moved in the near term. Your best bet in the pool might be someone from the GOP, frankly. I'll stick with Kelly Ayotte. I wanted to pick Zombie Reagan but evidently … he's already declared.


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Friday: Art appreciation day at the ROM
The Royal Ontario Museum offers free admission from 4:30 PM onwards
every Friday. Simon suggested heading over there for a bit of cultural
appreciation, and we had fun walking around before my 8:30 dinner with
the folks I met at the Oriented networking event.
I always find Japanese woodblock prints fascinating, and we spent some
time in that gallery. I'm also drawn to calligraphy, classical
sculptures, and realistic paintings (particularly those with literary
or mythological references, like classical paintings). I like room
reproductions, too – glimpses of what people's lives were like in the
past or how they are elsewhere. I like pieces with stories.
We'll go back one of these Fridays. It would be nice to contemplate a
single thing and learn its story. Too bad there are no Wikipedia
kiosks in the museum. Do you think there'll be wireless?


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Hi steve, did you see my email in the latest Muscle car masters magazine? I responded to your story about the first wellington street race in a 'whimsical' tone.. heh... My son will hate me now!
Hey Brett, its OK I just moved it so its a new thread now. Thanks again, very cool.
Hey there Brett, its great to have you on board. Re that Gerry Marshall footage, thats such cool footage I think you should start a new thread just to show it on its own, rather than include it in the Crystal Palace thread. If you start a new thread on it I'll remove the other post off the Crystal Palace thread, that way more people will get to see it. Thanks Steve


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This is the place for all student to place messages about student activities, finding clinical placements and just having a general chat with other students around the world.
Use this control to limit the display of threads to those newer than the specified time frame.
Allows you to choose the data by which the thread list will be sorted.
Order threads in...
Note: when sorting by date, 'descending order' will show the newest results first.


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Two Canadians and two Americans who were kidnapped in Nigeria's north-central Kaduna state on Tuesday have been freed and are in good condition, police said Saturday.
Police and a special anti-kidnapping squad rescued the foreigners in the Kagarko local government area Friday night after a massive manhunt, state police commissioner Agyole Abeh said.
"No ransom was paid. It was the efforts of the police through the directives of the Inspector General of Police that led to their release," he said.
One suspect was arrested in connection with the kidnapping and police were on the trail of remaining suspects, Abeh said.
The foreigners have been taken to the capital, Abuja, Kaduna state police spokesman Mukhtar Aliyu said.
"They are in good condition but due to trauma they have to undergo medical observation." Aliyu said.
Gunmen ambushed the foreigners Tuesday as they travelled from Kafanchan in Kaduna state to Abuja. Two police escorts were killed in what police called a "fierce gun battle."
The Americans and Canadians have not been publicly identified. Aliyu earlier said they are investors setting up solar stations in villages around Kafanchan.
Elizabeth Reid, a spokeswoman for Global Affairs Canada, said Canadian officials worked closely on the ground with the Nigerian government.
She said in an email that they have "been in regular contact with the Canadian families and the employer to provide assistance and support."
Kidnapping for ransom is common in Nigeria, especially on the Kaduna to Abuja highway. Two German archaeologists were seized at gunpoint last year less than 100 kilometres northeast of Abuja and later freed unharmed. Sierra Leone's deputy high commissioner was taken at gunpoint on the highway in 2016 and held for five days before he was let go.
Victims typically are released unharmed after ransom is paid, though security forces have rescued a few high-profile abductees. A number of bandits, including herdsmen, have been arrested.
Ibrahim Abdul'Aziz and Sam Olukoya, The Associated Press


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Kellar Grist Mill
Location: N. Base Road, 0.5 mile south of Brewersville, 0.5 mile north of the Sand Creek bridge, north of North Vernon. (Jennings County, Indiana)
Erected 1997 Indiana Historical Bureau and Jennings County Historical Society.
Adam Kellar began constructing a stone mill race on Sand Creek, 1813, and opened grist mill, 1823. Mill was important to local economy and was an impetus for development: state road to mill established, 1834, and Brewersville founded, 1837. Flatboats carried mill products as far as New Orleans. Mill was closed after damage in 1937 flood.
Business, Industry, and Labor, Transportation


text:
(CNN) -- Rapid-fire TV news bulletins or getting updates via social-networking tools such as Twitter could numb our sense of morality and make us indifferent to human suffering, scientists say.
Scientists say updates on networking tools such as Twitter are often too quick for the brain to fully digest.
New findings show that the streams of information provided by social networking sites are too fast for the brain's "moral compass" to process and could harm young people's emotional development.
Before the brain can fully digest the anguish and suffering of a story, it is being bombarded by the next news bulletin or the latest Twitter update, according to a University of Southern California study.
"If things are happening too fast, you may not ever fully experience emotions about other people's psychological states and that would have implications for your morality," said researcher Mary Helen Immordino-Yang.
The report, published next week in Proceedings of the National Academy of Sciences Online Early Edition, studied how volunteers responded to real-life stories chosen to stimulate admiration for virtue or skill, or compassion for physical or social pain. iReport.com: Growing pains for Twitter, Facebook?
Brain scans showed humans can process and respond very quickly to signs of physical pain in others, but took longer to show admiration or compassion.
"For some kinds of thought, especially moral decision-making about other people's social and psychological situations, we need to allow for adequate time and refection," said Immordio-Yang.
She said the study raises questions about the emotional cost, particularly for young people, of heavy reliance on a torrent of news snippets delivered via TV and online feeds such as Twitter.
She said: "We need to understand how social experience shapes interactions between the body and mind, to produce citizens with a strong moral compass."
USC sociologist Manuel Castells said the study raised more concerns over fast-moving TV than the online environment.
"In a media culture in which violence and suffering becomes an endless show, be it in fiction or in infotainment, indifference to the vision of human suffering gradually sets in."
Research leader Antonio Damasio, director of USC's Brain and Creativity Institute, said the findings stressed the need for slower delivery of the news, and highlighted the importance of slow-burn emotions like admiration.
Damasio cited the example of U.S. President Barack Obama, who says he was inspired by his father, to show how admiration can be key to cultural success.
"We actually separate the good from the bad in great part thanks to the feeling of admiration. It's a deep physiological reaction that's very important to define our humanity."
Twitter, which allows users to swap messages and links of 140-characters or less, says on its Web site that it sees itself as a solution to information overload, rather than a cause of it.
This function, It says, "means you can step in and out of the flow of information as it suits you and it never queues up with increasing demand of your attention."


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Firefox 4 is gearing up for full launch! We're really excited about Firefox 4, with a streamlined Add-ons Manager, and numerous other performance and UI improvements.
Firefox 4 Beta is now API frozen, so if you haven't already done so, please make sure your add-on is compatible. Firefox 4 is a significant upgrade that may require a little more work to be done to make sure your add-on works than in previous Firefox releases.
Jorge Villalobos has outlined the changes to Firefox 4 that may affect add-on compatibility. If you have any further questions, or concerns, or know of any breaking changes that are not listed, please post in this forum thread, or join #extdev on irc.mozilla.org for real-time assistance.
Don't forget, Firefox 4 Beta for mobile is available in the Android Market and preparing for final release. Learn more about how to make your add-on mobile compatible.
Firefox 4 Add-on collection competition
To celebrate Firefox 4's arrival, we are launching a new add-on collection, which will showcase some of the best add-ons for Firefox 4. The collection will be promoted for two months after Firefox 4 is launched, through the Add-on Manager, our Add-ons Gallery, Facebook, the Rock Your Firefox blog, and through Twitter, among other channels.
To have a chance of being featured in the Firefox 4 add-on collection, once your add-on is ready – email us at email@example.com with "Add-on competition" in the subject line, a link to your add-on, your name, and a brief description of your add-on's functionality. The winning 10 add-ons, as chosen by the Mozilla Add-ons team, will be promoted from the Firefox 4 launch day.
Get your entries in by March 6th 2011. If you win, we'll reach out to you to let you know shortly before the launch of Firefox 4. Download the contest rules here.


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Credit rating agencies are likely to hold off passing judgment on the U.S. credit rating until they have a clearer picture about the fate of the debt ceiling and longer term plans to reduce borrowing.
The New Year fiscal cliff agreement between the White House and Congress raised taxes on the richest Americans but postponed much of the toughest political wrangling on automatic spending cuts for another two months.
Also, the bill does not address the $16.4 trillion debt ceiling, which was hit on Monday. Instead, the Treasury Department will deploy "extraordinary measures" to allow additional borrowing of about $200 billion, in effect buying the United States about two months to raise the official limit.
The last time Congress negotiated the debt ceiling it prompted Standard & Poor's to strip the country of its coveted AAA credit rating. The agency criticized ineffective decision-making in Washington and the lack of a plan to stabilize the country's debt in the medium term.
S&P said in late December it still held that view, and repeated a warning that the United States could face another downgrade by 2014, or sooner, if Congress doesn't come up with a plan to reduce the national debt.
Related: Fiscal cliff deal boosts world markets
Fitch and Moody's both kept their top AAA ratings in place after the S&P downgrade but have warned of the risk of downgrades.
Moody's said Monday it would be watching how Washington handles the nearly simultaneous issues of the debt ceiling and spending cuts. It reiterated what it said in September -- that a downgrade was likely if lawmakers were unable to agree on a long-term debt reduction plan.
"Failure to reach even a temporary arrangement to prevent the full range of tax increases and spending cuts implied by the fiscal cliff and a repeat of the August 2011 debt ceiling episode would indicate that the general election had not resolved the political gridlock in Washington and would probably result in a sovereign rating downgrade," Fitch said last month.
With a temporary agreement now in place, and the debt ceiling debate deferred, an imminent downgrade seems unlikely. But the threat hasn't gone away.
"Failure to reach agreement on raising the debt ceiling in a timely manner -- weeks in advance rather than just a single day before the funding capacity of the federal government is exhausted as happened in August 2011 -- would raise questions about US governance on fiscal matters and undermine confidence in the United States as a reliable borrower and prompt a formal review of the U.S. rating," Fitch said in its global sovereign outlook.
The impact any further downgrades would have, however, remains unclear. U.S. borrowing costs fell following S&P's 2011 move, and a similar pattern has been seen when other AAA-sovereigns have suffered the same fate. Yields on French government bonds have declined since it lost its AAA rating from Moody's in November.


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WASHINGTON -- For the first time in its storied -- some say
cursed -- history, the cover of EA Sports' "Madden NFL" video game
will feature two cover athletes: Pittsburgh Steelers safety Troy Polamalu and Arizona Cardinals receiver Larry Fitzgerald.
"Being on the cover of 'Madden' is a real honor," Fitzgerald
said Friday after Electronic Arts made the announcement. "And
sharing it with a talent like Troy is really special."
The shared cover of "Madden NFL 10," which arrives in stores
Aug. 14, has something for everyone: Polamalu is a defensive AFC
player and Fitzgerald an offensive NFC player.
EA Sports senior product manager Anthony Stevenson called the
two Pro Bowlers "exemplary examples of the epic battle between
offense and defense in the NFL."
Both played in last season's Super Bowl, which the Steelers won
in a 27-23 nail-biter. Both athletes are known for their long,
helmet-defying hair.
Steel City football fans should be
particularly happy, because Fitzgerald played college ball at the
University of Pittsburgh. And he was also on the cover of EA's "NCAA
Football 2005."
EA's football franchise is feared for its mysterious "Madden
curse": Previous cover models like Donovan McNabb, Shaun Alexander
and Vince Young have suffered injuries during their "Madden"
Fitzgerald, however, was defiant. "I didn't think about the
curse," he said. "If both of us have MVP years, everybody will be
chomping at the bit to get on the cover."


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2225 NE Martin Luther King Jr. Blvd., 284-3366, oxpdx.com.
[SOUTH AMERICAN STEAKS] Martin Luther King Jr. Boulevard is burning. The scent of fire still wafts from the embers of the Monroe Apartments—a five-story apartment building torched to the ground in an apparent August arson—and only grows stronger seven blocks south, at the most celebrated chunk of gentrification in this street's history. The secret weapon of Ox is its ventilation system, which bathes adjacent waiting room Whey Bar and the surrounding neighborhood in the smell of wood-fired meats. It's as if the stainless-steel, cuboid grill were a portal to a Cannon Beach bonfire. Yet nothing I tried on the Argentine-inflected menu quite matched this anticipation. The 16-ounce rib-eye, the house anchor at $38, exceeds any other Portland steak-house cut, but doesn't rival the revelatory beef presentations offered at Old Salt or Castagna. However, it's much, much bigger—and nearly triples in size if you spring for 36 ounces at $75. Brawny overkill is the dominant mode at Ox, whether it's the hulking pork loin chop ($22, in a smart maple brine) or the $13 sauteed mushrooms, which include foie gras in an already butter-soaked bowl. Everything exists to remind you of its largess, and the effect, while truly luscious, is also troublingly rich. AARON MESH.
Ideal meal: Clam chowder with smoked marrow ($13), the rib-eye, the mushrooms.
Best deal: The $5 empanadas, which bear no small resemblance to Whiffies Fried Pies.
Pro tip: The $5 ricotta next door at Whey Bar features the spectacular house chimichurri, and is my favorite item on the premises.
5-10 pm Tuesday-Thursday and Sunday, 5-11 pm Friday-Saturday. $$$.
WWeek 2015


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What "I'll Have Another" Loses After Being Scratched from Belmont and Not Winning Triple Crown
Had the horse won at Belmont Park on Saturday, I'll Have Another would have become the 12th horse to capture horse racing's Triple Crown by virtue of consecutive victories in the Kentucky Derby, Preakness Stakes and Belmont Stakes.
So, besides famously becoming the first horse since Affirmed in 1978 to win all three races, what does I'll Have Another NOT get now that it can't win the Triple Crown?
Claims on a 62 percent share of the $1 million purse — or $620,000 — awarded by the Belmont Stakes. The second-place horse receives 20 percent, while 11 percent is given to the third-place horse. Obviously, I'll Have Another has already won the greatest shares of the Kentucky Derby and Preakness Stakes purses.
Since only 11 horses have managed to win the Triple Crown, there can be no question that, regardless of financial windfall, a Triple Crown winner receives lasting fame for its accomplishment. In this modern age of instant marketing and total merchandising, it is easy to imagine that the first Triple Crown winner in 34 years would also have many possible sponsorship and branding opportunities afforded to it.
The winner receives the Belmont Stakes trophy — a Tiffany-made silver bowl with a cover — and a carnation blanket. Triple Crown winners are also awarded a special Triple Crown Trophy. Commissioned by the Thoroughbred Racing Association and created by jeweler Cartier, the Triple Crown Trophy is a three-sided vase with each side equating to one of the series races.
When the racing career of a Triple Crown winner, or any successful race horse, has ended, the horse is often further syndicated, meaning additional shares of ownership in the horse are offered. People buy those shares because when the horse is put out to stud, it can be quite lucrative for its ownership. For instance, Affirmed sired over 80 stakes winners who earned more than $44 million.
What Horses Don't Win
From 1986-1995, Chrysler Motors sponsored a Triple Crown bonus that would have paid $5 million to a Triple Crown-winning horse. The sponsorship was then picked up by Visa USA from 1996-2005. Since no horse won the Triple Crown during those years, a $1 million bonus was awarded to the horse who accumulated the most points by virtue of its finishes in the three-race series. Both the $5 million bonus and the $1 million bonus are no longer offered.


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Item #QTHR0P
Size:Hand Repair Balm 8oz
What is Qtica Intense Overnight Hand Repair Balm
A thick, rich hand balm for the relief of severely dry, damaged hands
What Qtica Intense Overnight Hand Repair Balm Does
Hands look and feel younger and smoother with QTICA Overnight Intense Repair Balm. The rich, thick balm soothes severely dry, irritated and cracked hands with an intense formula of honey, beeswax, essential oil and vitamins A, C, and E. Anti-aging Retinol Palmitate softens fine lines and speeds cellular renewal so hands never betray age. Used by outdoor athletes and those with extremely thin, sensitive skin to replenish moisture lost during daily activities while preventing further damage.
How to Use Qtica Intense Overnight Hand Repair Balm
Professional use: Apply a small amount to the hands as an instant smoother. Can be used with heat and paraffin for a more deeply penetrating therapy. Home use: Apply a pea-sized amount to each hand and massage until absorbed. For best results use daily.
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-Freedom, MD
Consumer Review
I bought this during the huge Black Friday sale. It is THE BEST decision I`ve made for my hands yet. My hands have never felt silkier and that`s with just using it once at night. I could not recommend this treatment enough, especially if you`ve tried everything else and still suffer with severely dry hands. I used to absolutely HAVE to apply lotion IMMEDIATELY after washing my hands because they`d feel tight and uncomfortable - I still apply lotion after washing out of habit but I`ve noticed that the tight feeling is GONE after hand washing. It`s crazy. I wish Qtica products would go on sale more often; there are some serious gems out there that people probably never would have discovered had it not been for this sale. Please do it more often! :)
Consumer Review
Qtica Intense Overnight Hand Repair Balm 3oz TubeAmazing
Consumer Review
Qtica Intense Overnight Hand Repair Balm 3oz TubeThe Real Deal
This stuff WORKS. After buying this and the lip repair, I`ve stopped using all of my other shea butter and "intense restorative" hand and lip treatments. It does smell a little like lanolin, but it`s subtle. It soaks in quickly and doesn`t budge. At night, I put on a thick coat and wear cotton gloves and this has saved my dry, cracked hands. I`m a healthcare provider in a very dry climate and I used to cringe every time I washed my hands during the day because my skin would get dry, flaky, itchy and start cracking over my knuckles; now I can finally keep my skin in good shape in spite of the constant washing. Because it`s so thick and soaks in so quickly, I find I don`t go through it as fast as I did my other lotions so it`s proving itself to be more cost-effective, which is a bonus. Qtica has definitely earned my loyalty.
Location-SLC- Utah
Salon Review
Qtica Intense Overnight Hand Repair BalmMust have for hubby
My husband is a mechanic so his hands are always a disaster. I bought this at a trade show in Chicago with the hope that it would fix his hands. I have to say that this product did what no other lotion could do for the past 5 years. This product really saved his hands and made his hands that much more pleasant to hold. My only complaint is that because it is so thick, you can only use it at night. I wish he could use it during the day too.
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Jacelyn may not have been knighted until Pyke, but he did have a surname, which implies he had noble/knightly ancestors somewhere back there, though his might well have been a cadet branch fallen low in the world. I don't think this was established either way.
A question that crops up concerning the two old River King dynasties -- is it wrong to assume that one of them was the line of the final River Kings, ended by the ancestors of the Storm King Arrec, and that the other (as Theon recollects in his first chapter in Clash of Kings) is the line ended by the old King of the Iron Islands whose slaughter of the then River Kings sons led to the naming of the Bloody Keep?
A logical assumption, and maybe half true. There were actually more dynasties in the riverlands than these two... but so far I've only come up with two names. The riverlands have been much warred over. The Mudds were the last of the First Men to rule the Trident, I seem to recall; it was Andal invaders who put an end to that line.
Is there any particular reason why the Dornish arms tend to be so . . . macabre?
A violent history. Particularly the mountain houses, who lived by raiding across the borders into the marches, feuded with each other endlessly, and were the first to face any invaders.


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With Caprica Season 1.0 about to be released on DVD, I think this is a great time to revisit its predecessor. It isn't often that my husband and I can both sit down and enjoy the same TV series, but when I brought home Battlestar Galactica: Season 1 from the library, we were both instantly hooked.
The show starts off with a familiar concept: a few decades ago, humans created artificial intelligence called Cylons in order to make their lives easier, but the Cylons eventually waged war on their human masters. A truce was declared, and the Cylons weren't heard from for 40 years. But just as the fleet's oldest ship (the Battlestar Galactica) is about to be decomissioned, the Cylons return and attack the colonies, leaving only about 50,000 humans alive. All while being hunted by the Cylons, the last living humans must search the galaxy for their new home: a mythical place called Earth.
With a cast of compelling and complex characters (including Galactica's Commander, his son the pilot, the newly sworn in President of the colonies, a pilot with a BIG secret, and a morally conflicted scientist), the show is not just another action-packed sci-fi adventure. It is also filled with drama, political strife, theological questions, and even some romance here and there. The twists and turns are shocking, and the plotlines really make you think about our society today. The way the seasons are packaged is a little annoying (it goes season 1, 2.0, 2.5, 3, 4.0, and 4.5) so it's important to make sure you don't accidentally skip a season. I could write pages and pages about this show, but I think I should stop now so that I don't ruin any surprises. Trust me, you don't want to be spoiled. Stop by the library to pick up a copy of Season 1. I can almost guarantee you'll be coming back for Season 2.0 within days.


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Douglas Menuez Photography Collection
The Douglas Menuez Photography Collection is the complete archive of award-winning documentary photographer Douglas Menuez. The archive includes Menuez's editorial photojournalism and fine art documentary work, as well his commercial projects. Included in the archive are more than 250,000 photographs documenting the rise of Silicon Valley. These photographs focus primarily on the computer and semiconductor industries, venture capital deals, startups, and Internet companies. Menuez had virtually unlimited behind-the-scenes access for these photographs. Some of the photographs have been published in national magazines, including Fortune, Time, and Life, but many are available only in this collection. Stanford's digitized images represent just a sample from the collection.
Menuez's rise to prominence began as an intern for the Washington Post, and continued with assignments for national publications, including Time, Newsweek, and Fortune. His social documentary work has covered stories such as the AIDS crisis, the famine in Ethiopia, and the destruction of the Amazon. His work has appeared in several "Day in the Life" books, and the 24 Hours in Cyberspace website and book. In 1987, he began a decade-long project to document the culture of high-technology development and business in Silicon Valley. He published Defying Gravity: The Making of Newton in 1992 (with an introduction by Paul Saffo and text by Markos Kounalakis). His most recent book, Heaven, Earth, Tequila: Un Viaje al Corazón de México, documents Mexican culture and traditions and was published in 2005.


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The Wish Tree by Kyo Maclear and illustrated by Chris Turnham has quickly become a family favorite. A story about Charles, a young boy that wants to find a wishing tree. With his trusty companion Boggan, they head out together on a journey to find the wishing tree and along the way learn a couple lessons on helping others.
Here is a little sneak peek into our interview with author Kyo Maclear.
{Q} "The Wish Tree" encourages exploration, giving, and celebrating the unexpected. As you look toward future books, what are the main messages you desire to relate to young readers through storytelling?
{A} What I hope to relate is less an overt message than a general sensibility. I think we're living in a fairly disconnected time (despite our relentless digital connectivity) and I'd like to model a sense of connection and care–care for art, for story, care for unbalanced worlds, for non-human life, care for humor and community, for passion and creativity—and, always, care and openness in the face of the unexpected.
You can read the rest of the interview in Babiekins Print Issue 9!
For a limited time, get a free signed print and card set by illustrator Chris Turnham when you buy a copy through Chronicle Books!
Want to win a copy of the book? Follow us on instagram and learn how to win!
Photo: Kim Ruth | Styling Priscila Barros | Tent | Outfit


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Today Rockstar added 10 new jobs created by different users from within the community. Find the full information about the GTA V update see below.
LSC Great Eight – Created by DrAtomic1
While it may look like a simple figure 8 track at first glance, the changes in elevation and tighter hairpins require a steady hand and intense concentration. Running around different levels of the Olympic Freeway this course will challenge all aspects of your driving. A strong octo-theme runs through this race: as DrAtomic1 points out in the description, the track itself is 0.8 miles long, and the maximum number of players is, you guessed it, 8. The map view of LSC Great Eight on the right, and the aerial shot on the left.
Dirt Track Derby – Created by N8thok
While there are hundreds of Jobs arranged around the horse racing track in the Palomino Highlands, we picked out N8thok's effort due to the considered placement of obstacles and pickups around the track that change this from a simple lap race to a white knuckle derby. With 16 players jostling for position, the slightest nudge could force you into the back of a burnt out bus, or off the track entirely. Masters of the art of drifting should be able to nail the curve corners and slingshot their vehicles into the straight sections. Final positions in the race will be decided by inches, the smallest mistake could be fatal.
Observe and Race – Created by The_Gemte
In this one, 3 quick laps of the circuit leading up to the Observatory have been laid out using a variety of barriers to make for a very fluid and natural race. Overtaking skills will be put to the test as the only straight comes in the form of a narrow tunnel section where race leaders can easily defend against drifters. Corners will be your only option to snatch the lead, so aim for the racing line, brake late and hope for the best!
Getting High and Low – created by El_Cactus
Precision is the name of the game in this high octane motorbike race along the narrow dirt paths just above Cassidy Creek. Maintaining control of your ride is absolutely essential as overhanging pine bows could take you out at any moment. Go easy on your first run, the corners come thick and fast and the only way to win is to make the fewest mistakes. Anyone reaching the end without spinning off the path and falling into the creek below at least once should be pretty pleased with themselves. Breathtaking views of Blaine County. Getting High and Low(left) and Through The Grapeseed (right).
Through The Grapeseed – Created by LoveLikeJazz
As Creator LoveLikeJazz describes it, this is a "lengthy lap race around Grapeseed with lots of long stretches and a few tricky turns. Watch out for those Sandkings, they think they own the road." Also, watch out for the stretch that goes the wrong way up the Senora Freeway, adding an extra element of danger to each lap. Avoid oncoming traffic to gain the advantage over your fellow racers, and keep an eye out for some spectacular crashes.
Sandy Shores Circus – Created by datwista111
Creator datwista111 modestly describes Sandy Shores Circus as a "simple race", belying the difficulty of the 45 degree turns around Sandy Shores town that will send cars criss-crossing each other all over. There are a few extra features of this race that really make it stand out, including crashing through a fence and into a resident's garden and a final straight that results in a high speed jump straight into the Alamo Sea… just the thing to cool down screaming hot engines.
Senora Desert Hills – Created by: ZardozToast
"Enjoy the best switchbacks in Blaine County with this winding off-road race up and down the hills of the Grand Senora Desert." A long and winding race that was selected for the unique way it allows players to drift down several dirt roads on the hills of the Senora Desert. Expert control and vehicle selection is essential in order to avoid drifting off the edge of a hill and down into the rocky valley below. Switchbacks through the undulating terrain in Senora Desert Hills
Nurburgring – Created by Mr_Grandis
The latest real-world homage to get a verification nod is this impressive take on Germany's famed Nurburgring. As Mr_grandis describes it is a "very technical and dangerous track with blind corners, bumps and long straight road." Recreated around Banham Canyon, Tongva Hills, Great Chaparral and Vinewood Hills, we like the way it challenges endurance and driving skill in equal measure.
Battle GTA – Created by KS-GTA
In the swamps outside Fort Zancudo KS-GTA, lone member of The Assassins Monks, has set up a pitched battle for 2 teams featuring power weapons and heavy machinery. The key to the success of this Deathmatch is balance: a cluster of incendiary props in the center field provides adequate cover for an infantry battle while powerful weapon pickups such as RPGs provide a fighting chance against aircraft. This is an excellent map for Crews to put their communication and teamwork skills to the test. The scene is set. Battle GTA and Paintball!
Paintball! – Created by yoduhh62
A flat expanse of sand on Del Perro Beach is transformed into a dynamic and challenging Speedball-style arena. With skillfully placed props like sandbags, construction fences, wrecked vehicles and tires, this Deathmatch forces players to dart between cover and expose themselves to gunfire when dashing for powerful weapon pickups. Stealth and timing are key here, and we recommend using teamwork to create distractions while you outflank and outmaneuver your enemies.


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Solargraphy at sunny Paranal
Solargraphy, the art of using a single long-term exposure with a pinhole camera to photograph the movement of the Sun over the course of many weeks, helps show just why Cerro Paranal in northern Chile makes the perfect home for ESO's Very Large Telescope (VLT). The pinhole camera, made from a small film canister and a piece of photographic paper, was placed on the roof of the VLT control building by Gerd Hüdepohl from 15 October to 26 December 2009, covering spring in the southern hemisphere. The white streaks across the top of the image are the Sun's progress across the sky over the whole period. When clouds come between the Sun and the camera, breaks in the streak form but, as can be seen here, no clouds obscured the sky during the entire exposure. Perfect astronomy weather in other words! The VLT's Unit Telescope 1 is visible as a ghostly outline at the bottom of the picture.
The idea for creating the solargraphs at ESO's telescopes came from Bob Fosbury, an astronomer based at ESO headquarters in Germany, after learning about the technique from Finnish artist Tarja Trygg. Trygg provided cameras — basically cylinders with a hole and a piece of unexposed photographic paper mounted along the inner wall — and Fosbury had Observatory director Andreas Kaufer deliver the cameras, known as "cans", to ESO's observatory sites in Chile and then collect them four months later for final processing by Trygg. "It's an absolutely unique image," Fosbury says. "I've never seen unbroken solar trails like this before in images exposed from all around the world."
The colours appearing in this pinhole camera picture are not related to the actual colours of the scene. The colour comes from the appearance of finely divided metallic silver growing on silver halide grains. With solargraphic images, the photographic paper is not developed but simply scanned with a normal colour scanner after exposure and then "inverted" — switched from negative to positive — in the computer. This reveals the latent image, which in a normal photograph consists of around ten silver atoms per billion atoms of silver halide grain and is usually invisible. On continued exposure however, the latent image clumps grow so that the first visible signs of an image are yellowish, which then darkens to sepia and finally to a maroonish-brown hue as the particle size increases. Eventually the maximum exposure produces a slate grey shade.
In this solargraph you can see curved reflections of the solar image forming a "caustic" about one third of the way across the image. Such effects are common in solargraphs when the Sun is near the edge of the field and are created by reflections from the white paper where the photographic paper departs from a circle and flattens near its ends.
Credit:ESO/R. Fosbury/ T. Trygg/ G. Hüdepohl (atacamaphoto.com)/ A. Kaufer
About the Image
Id: | potw1011a |
Type: | Photographic |
Release date: | 15 March 2010, 08:50 |
Size: | 1998 x 1196 px |
About the Object
Type: | Solar System : Sky Phenomenon : Light Phenomenon : Sunrise-Sunset |
Category: | Paranal |


text: SHRED(1) FSF SHRED(1) NAME shred - delete a file securely, first overwriting it to hide its con- tents SYNOPSIS shred [OPTIONS] FILE [...] DESCRIPTION Overwrite the specified FILE(s) repeatedly, in order to make it harder for even very expensive hardware probing to recover the data. Mandatory arguments to long options are mandatory for short options too. -f, --force change permissions to allow writing if necessary -n, --iterations=N Overwrite N times instead of the default (25) -s, --size=N shred this many bytes (suffixes like K, M, G accepted) -u, --remove truncate and remove file after overwriting -v, --verbose show progress -x, --exact do not round file sizes up to the next full block -z, --zero add a final overwrite with zeros to hide shredding - shred standard output --help display this help and exit --version output version information and exit Delete FILE(s) if --remove (-u) is specified. The default is not to remove the files because it is common to operate on device files like /dev/hda, and those files usually should not be removed. When operat- ing on regular files, most people use the --remove option. CAUTION: Note that shred relies on a very important assumption: that the filesystem overwrites data in place. This is the traditional way to do things, but many modern filesystem designs do not satisfy this assumption. The following are examples of filesystems on which shred is not effective: * log-structured or journaled filesystems, such as those supplied with AIX and Solaris (and JFS, ReiserFS, XFS, Ext3, etc.) * filesystems that write redundant data and carry on even if some writes fail, such as RAID-based filesystems * filesystems that make snapshots, such as Network Appliance's NFS server * filesystems that cache in temporary locations, such as NFS version 3 clients * compressed filesystems In addition, file system backups and remote mirrors may contain copies of the file that cannot be removed, and that will allow a shredded file to be recovered later. AUTHOR Written by Colin Plumb. REPORTING BUGS Report bugs to <email@example.com>. COPYRIGHT Copyright (C) 2002 Free Software Foundation, Inc. This is free software; see the source for copying conditions. There is NO warranty; not even for MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. SEE ALSO The full documentation for shred is maintained as a Texinfo manual. If the info and shred programs are properly installed at your site, the command info shred should give you access to the complete manual. shred (coreutils) 4.5.3 October 2003 SHRED(1)